<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Document</title>
	<style>
	body{background-color: #ccc;}
	</style>
</head>
<body>
	<input type="text" id="input">	

<script>
	var input = document.getElementById('input');
	input.onkeyup = function(){
		parent.main[0].innerHTML = this.value;
	};	
</script>
</body>
</html>